Azlactone-functional polymeric supports have been prepared according to the methods disclosed in European Patent Publication 0 392 783 (Coleman et al.) and in European Patent Publication 0 392 735 (Heilmann et al.). In both of these publications, examples show methods of preparation which involve the homopolymerization or copolymerization of azlactone-functional polymers to become the polymeric support.
Azlactone-functional moieties are expensive and valuable. Preparation techniques which cause azlactone-functional moieties to be occluded from accessible use needlessly wastes the valuable azlactone functionality.
Also, there is a desire to place azlactone-functionality only at surfaces of a support where chemical or physical interaction with other materials, particularly biologically active materials can occur. Process IV described in European Patent Publication 0 392 735 discloses a method for coating azlactone-containing polymer at surfaces of substrates. Also, European Patent Publication 0 392 735 within the disclosure of Process IV and in Example 22 thereof identifies a desire to employ azlactone-containing monomers in the coating process to polymerize the monomer(s) in place.
There are a myriad of supports which have specific geometries useful for physical interaction with materials, particularly biologically active materials. These supports have specific physical and chemical characteristics: porosity, surface area, permeability, solvent resistance, hydrophilicity, flexibility, mechanical integrity, and other stability or feature in the use environment, etc., which must be retained for a pre-existing support to remain useful. For example, a microporous membrane will not remain useful as a filter if its porosity is harmfully compromised by the addition of an azlactone-functional moiety to its surfaces.
Monomeric 2-alkenyl-1,3-oxazolin-5-ones (which compounds and homologs thereof are referred to herein as 2-alkenyl azlactones) and copolymers thereof are known. Copolymers of 2-alkenyl azlactones and olefinically unsaturated monomers and coatings thereof are disclosed in U.S. Pat. No. 3,583,950 (Kollinsky et al.). Also, copolymers consisting essentially of a 2-alkenyl azlactone and an acrylic acid ester, and copolymerization thereof with vinylidene compounds having at least one hydroxyl group are disclosed in U.S. Pat. Nos. 3,488,327 and 3,598,790 (both to Kollinsky et al.). U.S. Pat. No. 4,695,608 (Engler et al.) discloses a bulk polymerization process for free radical polymerization of a vinyl monomer and a monomeric alkenyl azlactone or a macromolecular monomer with a molecular weight of less than about 30,000 in a wiped surface reactor such as a twin-screw extruder. Free radical initiator systems comprising a combination of reagents are useful in the process. Incorporation of alkenyl azlactones into acrylate pressure-sensitive adhesives improves the adhesives. Also disclosed in this patent are methods of preparation of 2-alkenyl azlactone monomers.